The present invention relates to an arrangement for supplying fuel from a supply tank to an internal combustion engine of a motor vehicle.
More particularly, it relates to an arrangement of the above mentioned type which has a supply aggregate connected at a suction side with a supply tank and at a pressure side with an internal combustion engine, and also branching conduits with a portion accommodating an ejector.
Supply arrangements of the above mentioned general type are known in the art. In the known arrangement the ejector is used for sufficient filling of a supply cup in which the supplying aggregate is arranged and for supplying the fuel from it to the internal combustion engine. Thereby even with a relatively empty fuel tank of the supply aggregate a fuel supply is provided, which guarantees that long increases can be overcome without problems. A further objective which can be solved with an .ejector is that the fuel contained in a two-chamber supply tank is available and is supplied by the ejector into the chamber from which the supply aggregate aspirates the fuel.
However, during starts of the internal combustion engine when only a relatively low voltage is provided in the drive motor of the supply aggregate and thereby a substantially reduced supply power of the aggregate takes place, a certain fuel quantity flows through the ejector in dependence on the nozzle diameter without producing in the gasoline injection system a pressure which is sufficient for the start. With low feed flow consumption and high system pressure a relatively small feed nozzle diameter is required. It however must be produced with narrow tolerances and is prone to dirtying in these conditions. The feed nozzle diameter can b made greater than approximately 0.4 mm. However, the above mentioned disadvantages during starts of the internal combustion engine are especially pronounced.
The required feed flow for a predetermined suction flow consumption corresponding generally to at least the maximum motor consumption, is substantially inversely proportional to the feeding pressure. With the advantageous branching at the pressure side of the supply system the feed pressure is substantially identical to the system pressure of the injection device of the internal combustion engine.